Rheumatoid Arthritis Flashcards
What is rheumatoid arthritis?
Chronic inflammatory disease, characterised by a symmetrical polyarthritis
Who gets RA?
Can present at any age, but peaks between 30-50
More common in women
What are the risk factors of RA?
Being female Smoking Genetics: HLA type Family history Obesity Exposure to certain environmental toxins
What is the synovium and where is it found?
A specialized connective tissue that lines the inner surface of capsules of synovial joints and tendon sheath
Makes direct contact with the synovial fluid lubricant, which it is primarily responsible for maintaining
The synovium is affected in rheumatoid arthritis. What happens to it?
Synovitis: inflammation of the synovium
Generation of new synovial blood vessels
Leucocytes are drawn to the synovium
The synovium proliferates an grows over the cartilage surface becoming a pannus
What is a pannus? What effect does in have on the joint?
An abnormal layer of fibrovascular tissue that results from hypertrophy of the synovium
The pannus destroys the articular cartilage and subchondral bone causing erosions
Which cells make up a pannus?
T lymphocytes Macrophages Plasma cells Fibroblasts Endothelium dendritic cells
What is the pathogenesis of RA?
Genetic mutations/problems cause the body to produce antibodies against the synovial tissue
Damage to the synovium occurs:
- synovitis
- pannus formation
Erosion of the bone:
- causes peri-articular osteoporosis
- leading to generalised osteoporosis
What are the clinical features of RA?
Symmetrical arthropathy:
- pain in joints
- loss of function
- deformity
- damage
Early morning stiffness lasting over 30 mins
Pain eases with exercise/use of joint
Non-articular + systemic features
Which joints are (and are not) affected in RA?
Most often hands and feet
But not the distal interphalangeal joint usually
Or dorsal or lumbar spine
Most other joints can be affected, always bilateral though
What are some non-articular features of RA?
Bursitis. tenosynovitis
Muscle wasting
Nodules:
- over pressure points, elbow, finger joints
- in pleura, pericardium, lung
Fever, fatigue, weight loss
Eye problems Neurological problems Anaemia Lung fibrosis Pericarditis/effusion Vasculitis
What is bursitis?
Inflammation of a bursa
Bursa = a small sac of synovial fluid
What is tenosynovitis?
Inflammation of a the fluid filled sheath containing synovium that surrounds a tendon
What is rheumatoid factor?
Is it present in al cases of RA?
An antibody against the Fc portion of the body’s IgG
It fights the body’s own antibodies
80% of RA cases are rheumatoid factor positive
In terms of RA, describe the structure of a nodule?
Ring of macrophages and fibroblasts surrounded by a cuff of connective tissue containing clusters of lymphocytes
In the centre is a fibrinoid necrotic core
